The increasing complexities of vehicle navigation systems, such as those used in aircraft, require a vehicle operator to be aware of many parameters relevant to the operation of the vehicle. In an aircraft, for example, a large number of parameters relevant to proper aircraft operation must be presented to a pilot using one or more avionics displays or instruments. The constant monitoring of these parameters typically requires the pilot's eyes to focus on or shift to one or more locations one or more displays or instruments. One parameter to be viewed by an aircraft pilot is vehicle speed deviation. Typical avionics displays provide a vehicle speed deviation indicator that requires a pilot to use his or her foveal vision, which is also known as the visual focus area, to derive useful information about the speed of an aircraft relative to a reference speed. However, the vehicle speed deviation indicator competes, with other parameter displays, for the attention of the pilot. As human eyes are designed to focus on a relatively small area at a single instant, it is physiologically impossible for the pilot to truly simultaneously maintain focus of his or her eyes on a display or readout of every parameter necessary to fly the aircraft.
Some current systems attempt to provide large amounts of information to a pilot by simplifying the display of certain information so that the information can be compacted into a smaller area. However, simplifying the display of information may equate to changing commonly accepted norms and terminology for displaying the information, and such changes can cause unwarranted confusion to pilots accustomed to the norms. In addition, compacting large amounts of information into a small area may increasingly crowd or clutter the display so that it is difficult to discern the displayed information. Further, if too much information is compacted into the viewer's visual focus area, the viewer may tend to shrink his or her visual focus area in response. The subconscious shrinking of the visual focus area of a viewer thereby defeats the purpose of compacting large amounts of information into a smaller focus area.
The current development of synthetic vision systems creates additional challenges for communicating information to an aircraft pilot. Known synthetic vision systems may display a three-dimensional rendering of an intended flight path. Focusing upon maintaining the aircraft within the intended flight path may prevent the pilot from ascertaining important cues, such as aircraft speed deviation, without shifting visual focus to another portion of the display—or to another avionics display altogether. Such a shift of visual focus increases the possibility that the pilot will not be able to maintain the flight of the aircraft along the intended flight path.
It is therefore an object of the invention to provide information to an operator of a vehicle in a manner that reduces the number of parameters upon which the eyes of the operator are required to focus.
It is a further object of the invention to visually provide information to an operator of a vehicle while the eyes of the operator are focused upon a display of other information.
It is a further object of the invention to visually provide relative speed information to an operator of a vehicle while the operator is focusing on a display of other information.
It is still another object of the invention to visually provide information on a synthetic vision display in a manner that does not require an operator to focus upon the information.
A feature of the invention is the use of visual reference cues or indicators positioned to communicate relative speed-related information to an operator without requiring the operator to focus on said cues or indicators.
An advantage of the invention is the reduction of the required eye movement of an operator to ascertain information relevant to the operation of the vehicle.